git.meshlink.io Git - meshlink/blob - src/edge.c

   1 /*
   2     edge.c -- edge tree management
   3     Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License along
  16     with this program; if not, write to the Free Software Foundation, Inc.,
  17     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "system.h"
  21
  22 #include "splay_tree.h"
  23 #include "edge.h"
  24 #include "logger.h"
  25 #include "meshlink_internal.h"
  26 #include "netutl.h"
  27 #include "node.h"
  28 #include "utils.h"
  29 #include "xalloc.h"
  30
  31 static int edge_compare(const edge_t *a, const edge_t *b) {
  32         return strcmp(a->to->name, b->to->name);
  33 }
  34
  35 static int edge_weight_compare(const edge_t *a, const edge_t *b) {
  36         int result;
  37
  38         result = a->weight - b->weight;
  39
  40         if(result) {
  41                 return result;
  42         }
  43
  44         result = strcmp(a->from->name, b->from->name);
  45
  46         if(result) {
  47                 return result;
  48         }
  49
  50         return strcmp(a->to->name, b->to->name);
  51 }
  52
  53 void init_edges(meshlink_handle_t *mesh) {
  54         mesh->edges = splay_alloc_tree((splay_compare_t) edge_weight_compare, NULL);
  55 }
  56
  57 splay_tree_t *new_edge_tree(void) {
  58         return splay_alloc_tree((splay_compare_t) edge_compare, (splay_action_t) free_edge);
  59 }
  60
  61 void free_edge_tree(splay_tree_t *edge_tree) {
  62         splay_delete_tree(edge_tree);
  63 }
  64
  65 void exit_edges(meshlink_handle_t *mesh) {
  66         if(mesh->edges) {
  67                 splay_delete_tree(mesh->edges);
  68         }
  69
  70         mesh->edges = NULL;
  71 }
  72
  73 /* Creation and deletion of connection elements */
  74
  75 edge_t *new_edge(void) {
  76         return xzalloc(sizeof(edge_t));
  77 }
  78
  79 void free_edge(edge_t *e) {
  80         sockaddrfree(&e->address);
  81
  82         free(e);
  83 }
  84
  85 void edge_add(meshlink_handle_t *mesh, edge_t *e) {
  86         splay_insert(mesh->edges, e);
  87         splay_insert(e->from->edge_tree, e);
  88
  89         e->reverse = lookup_edge(e->to, e->from);
  90
  91         if(e->reverse) {
  92                 e->reverse->reverse = e;
  93         }
  94 }
  95
  96 void edge_del(meshlink_handle_t *mesh, edge_t *e) {
  97         if(e->reverse) {
  98                 e->reverse->reverse = NULL;
  99         }
 100
 101         splay_delete(mesh->edges, e);
 102         splay_delete(e->from->edge_tree, e);
 103 }
 104
 105 edge_t *lookup_edge(node_t *from, node_t *to) {
 106         edge_t v;
 107
 108         v.from = from;
 109         v.to = to;
 110
 111         return splay_search(from->edge_tree, &v);
 112 }